Lamp-grip.



G. W. GOODRIDGE.

LAMP GRIP.

APPLICATION FILED AUG.10.'19|4.

Patented J 11116 13, 1916.

G/LBERT W. Ci'oook/aqs GILBERT W. GOODRIDGE, OF BBIDGEPORT, CONNECTICUT, ASSIGNOR TO THE BRYAN T ELECTRIC COMPANY, 013 BRIDGEPORT, CONNECTICUT, A CORPORATION OF CON- NECTICUT.

LAMP-GRIP.

Specification of Letters Patent. Patgnted Jung 13, 1916,

Application filed. August 10, 1914. Serial No. 856,085.

particularly to a device designed to prevent a lamp from backing out or a receptacle of the Edison type under the influence of vibration and the outwardly wedging action caused by the pressure exerted upon the more or less cone shaped la'mp base, after it has been screwed home in the receptacle.

ln the accompanying drawings, Figure 1 is .a broken elevation of a. lamp socket to which my invention is applied in one form;v

Fig. 2 is a broken elevation of thescrew shell taken at right angles to the position shown in Fig. 1; and Fig. 3 is a plan of the spring ring shown in the preceding figures.

My invention is here shown embodied in a lamp socket, but it is to be understood that it is applicable to lamp receptacles of any type.

The present socket is provided with the usual casing comprising cap 5 and shell 6 inclosing the insulating body 7 of the socket on which the screw shell side contact 8 is mounted in any convenient manner. As is generally understood, the lamp base is screwed into the socket and held by its threaded engagement with the screw shell side contact 8. In order to effect a gripping action upon the inserted lamp lease, 1 have longitudinally slottedthe screw shell at a plurality of points 9, so that the free end of the shell is susceptible of constriction under the influence of a suitable spring member. To offset this constriction I have screwed upon the exterior of the shell a ring 10 of spring metal such as tempered steel and of more or less elliptical shape. The long diameter of this ring exceeds, and the short diameter of-the ring is less than, the

normal diameter of the shell 8. C-onse quently when the ring is in adjusted position upon the shell, the pressure across the shorter diameter thereof-effects a constricting action upon the slotted end of the screw shell 8. The latter is thereby deformed from its normal cylindrical shape by the pressure of the spring ring 10. Upon the insertion of the lamp base, the latter is thus firmly less than the normal diameter of the screw- -tudinally slotted screw clamped and held by the spring ring against accidental reverse rotation or backing out.

To adjust the spring ring 10 in position on the shell 8, it is only necessary to compress the ring upon its longer axis until it assumes a circular shape, whereupon it may be threaded upon the exterior of the screw shell 8. It is of course desirable to position the ring as close to the outer end of the shell as is commensurate with the security of its adjustment, since the pressure thereof upon the segmentsof the shell is most effective at this point. 9 are diametrically opposite, as in the construction illustrated, the short diameter of I do not limit my invention to the precise details illustrated.

: I claim a s my invention 1-- p 1. A lamp receptacle comprising a longitudinally slotted screw shell side contact and spring means engaging a thread of the shell for constricting the free ends of'the'seg- Where the slots mental portions of the shell to eli'ect a gripping action upon aninserted lamp base.

.2. A'lamp receptacle comprising a longitudinally slotted screw shell side contact and a spring ring mounted exteriorly upon the segmental portions of the shell and Within the threaded area of the latter to constrict the same, substantially as described.

A lamp receptacle comprising a longitudinallv slotted screw shell side contact and I mounted exteriorly thereon an elliptical spring ring, the short diameter of Which-is shell.

4. A lamp receptacle comprising a longitudinally slotted screw shell side contact and mounted exterio'rly thereon an elliptical spring ring threaded. into position on said screw shell and having a short diameter less than the normal diameter of the screw shell. 5. A lamp receptacle having a deformable screw shell and spring means engaging the threaded portion of the shell for constricting the same against the entry of alamp base, substantially as described.

6. A lamp receptacle comprising a longishell side contact and mounted exteriorly thereon an elliptical In testimony whereof I have signed my spring ring, the short dlameter of which 1s name to this speclfication, in the presence 16 less than the normal diameter of the screw of two subscnbing witnesses.

. shell, said spring rim having an internal m w i l thread to facilitate the screwing of said ring GILBERJ (IQODRIDGE' into adjust-ed position on the screw shell Witnesses:

While the ring is temporarily deformed into H. W. BADEAU,

annular shape. N. A. Tums. 

